US5204891A - Focal track structures for X-ray anodes and method of preparation thereof - Google Patents

Focal track structures for X-ray anodes and method of preparation thereof Download PDF

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Publication number
US5204891A
US5204891A US07/785,122 US78512291A US5204891A US 5204891 A US5204891 A US 5204891A US 78512291 A US78512291 A US 78512291A US 5204891 A US5204891 A US 5204891A
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Prior art keywords
layer
anode
graphite
focal track
tungsten
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US07/785,122
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English (en)
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David W. Woodruff
Minyoung Lee
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General Electric Co
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General Electric Co
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Assigned to GENERAL ELECTRIC COMPANY A NEW YORK CORPORATION reassignment GENERAL ELECTRIC COMPANY A NEW YORK CORPORATION ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: LEE, MINYOUNG, WOODRUFF, DAVID W.
Priority to JP4282116A priority patent/JPH05217532A/ja
Priority to AT0208592A priority patent/AT399789B/de
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J35/00—X-ray tubes
    • H01J35/02—Details
    • H01J35/04—Electrodes ; Mutual position thereof; Constructional adaptations therefor
    • H01J35/08—Anodes; Anti cathodes
    • H01J35/10—Rotary anodes; Arrangements for rotating anodes; Cooling rotary anodes
    • H01J35/108—Substrates for and bonding of emissive target, e.g. composite structures
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J2235/00—X-ray tubes
    • H01J2235/08—Targets (anodes) and X-ray converters
    • H01J2235/083—Bonding or fixing with the support or substrate
    • H01J2235/084—Target-substrate interlayers or structures, e.g. to control or prevent diffusion or improve adhesion

Definitions

  • the present invention relates to x-ray tubes and in particular to high performance targets used in x-ray generating equipment, such as computerized axial tomography (C.A.T.) scanners. More particularly, the invention is directed to high performance rotating x-ray tube anode structures having focal tracks with improved adherence.
  • C.A.T. computerized axial tomography
  • Another patent expresses concern with the formation of tungsten carbide by reaction between a graphite disc, or carrier, and the tungsten target layer while accepting the in situ formation of a carbide layer of tantalum (or presumably of hafnium, niobium or zirconium).
  • the initial assembly of components consists of a graphite carrier upon which are successively deposited a first layer of iridium, osmium or ruthenium, a second layer of hafnium, niobium, tantalum or zirconium and then a target layer (e.g., tungsten).
  • the desired layer of carbide forms when, during operation of the x-ray tube, carbon diffuses across the first layer and reacts with the second layer.
  • carbide e.g., tantalum carbide
  • U.S. Pat. No. 3,710,170 is concerned with thermal stresses introduced in the rotary anode structure because of the difference in thermal expansion coefficients between tantalum carbide (U.S. Pat. No. 3,890,521) and the adjoining structure and between graphite (U.S. Pat. No. 3,710,170) and the adjoining structure.
  • certain metal carbide content is deliberately employed as part of the solder material.
  • a molybdenum-molybdenum carbide eutectic be prepared by placing graphite in contact with molybdenum and heating to about 2200° C.
  • Graphite which provides a low mass, high heat storage volume, remains a prime candidate for rotating anode structures of C.A.T. scanner x-ray tubes, particularly when the graphite member functions as a heat sink from which heat is dissipated as radiant energy as disclosed in U.S. Pat. No. 3,710,170 and U.S. Pat. No. Re. 31,568.
  • the aforementioned braze materials are characterized by their ability to react with tungsten, tungsten alloys, molybdenum, molybdenum alloys and also with graphite. Because the reaction of the interposed layer with graphite can only proceed at a temperature in excess of the temperatures that are reached by the rotating anode in service, even at the maximum service temperatures an intermediate platinum layer, for example, will act as a diffusion barrier for carbon to prevent the passage thereof through the platinum, where it would be able to form brittle tungsten or molybdenum carbide.
  • the intermediate layer e.g., platinum
  • the intermediate layer melts and become saturated with carbon.
  • liquid platinum can, over a period of time at a temperature just above the eutectic temperature, dissolve up to about 16 atomic percent carbon.
  • carbide will form at the interface.
  • the amount of time available for carbon to dissolve in the liquefied braze layer is, therefore, important and if the assembly being brazed remains at a high temperature for too long a period of time, a thick layer of carbide can form, which could delaminate during cooling or handling.
  • a temperature exposure of about 1800° C. for as little as about 5 minutes will result in a layer of molybdenum carbide about 0.003 inch in thickness.
  • the invention is directed to an improved x-ray tube anode comprising, a graphite anode body having a substantially damage free region and a focal track layer disposed on the region for impingement by electrons for producing x-rays.
  • the invention is further directed to a method of producing a graphite substrate having a shape formed surface substantially free of damage caused during the shape forming of the surface comprising, oxidizing a damaged layer of the graphite on the shape formed surface until an undamaged surface underneath the damaged layer is exposed.
  • FIG. 1 is an exemplar of a rotating anode x-ray tube, shown in section, in which an improved anode of this invention may be employed.
  • FIG. 2 is an enlarged partial sectional view of a graphite anode body provided with a shape formed surface having surface damage thereon.
  • FIG. 3 is an enlarged partial sectional view of the anode body provided with an undamaged surface.
  • FIG. 4 is an enlarged partial sectional view of the anode body provided with a microcracked rhenium diffusion barrier layer on the undamaged surface.
  • FIG. 5 is an enlarged partial sectional view of the anode body provided with an anode target layer deposited on top of the microcracked barrier layer to form the anode of the preferred embodiment.
  • FIG. 6 is an enlarged partial sectional view of another embodiment of the present invention.
  • FIG. 7 is an enlarged partial sectional view of yet another embodiment of the present invention.
  • FIG. 8 represents a photomicrograph of an enlarged view similar to a dendritic structure of a rhenium layer on a graphite anode body known in the prior art.
  • FIG. 9 represents a photomicrograph of an enlarged view of a continuous rhenium layer on a graphite surface.
  • FIG. 10 represents a photomicrograph of an enlarged view of delamination that results to the continous rhenium layer of FIG. 9 during a pyrolytic carbon infiltration step, i.e. sealing of the exposed portion of graphite anode body with an impervious coating of pyrolytic carbon.
  • FIG. 11 represents a photomicrograph of an enlarged view of a microcracked rhenium layer on a graphite surface.
  • X-ray Tube 10 comprises a hermetically sealed and substantially evacuated envelope 11.
  • Envelope 11 is generally made of x-ray transparent material, such as glass.
  • a cathode support partly sealed into the first end.
  • a cathode structure 13 comprising an electron emissive filament 14 and a focusing cup 15 is mounted on support 12.
  • Filament 14 is provided with a pair of filament conductors 16 for supplying heating current to filament 14.
  • Cathode structure 13 is further provided with an electronically grounded conductor 17 for maintaining cathode structure 13 at ground or maintaining a negative potential with respect to an anode 18 of x-ray tube 10.
  • Anode 18 (also referred to as target) is positioned in an opposing relationship with filament 14.
  • An anode body 21 of anode 18 generally has a disc shape and is typically made of materials such as molybdenum alloyed with titanium and zirconium, or carbon in the form of graphite.
  • a polycrystalline graphite is preferred.
  • the polycrystalline graphite customarily used for x-ray tube targets generally comprises graphite crystallites held together with a binder, such as coal tar pitch, which has been somewhat graphitized during the graphite forming process.
  • Medium density graphite in the range of about 1.75 to about 1.85 grams per cubic centimeter is most suitable.
  • Anode 18 is further provided with a focal track layer 19 on which electrons generated by filament 14 impinge to produce x-rays.
  • Focal track layer 19, as shown in FIG. 5, further comprises a diffusion barrier layer 32 contiguously disposed on a focal track region of surface 31 and an anode target layer 20 disposed on top of diffusion barrier layer 32. Diffusion barrier layer 32 prevents carbide formation of material used for anode target layer 20.
  • Diffusion barrier layer 32 is generally made of materials, such as rhenium, ruthenium or osmium. Rhenium is preferred.
  • Anode target layer 20 is generally made of tungsten or tungsten alloyed with rhenium, typically up to 15% by weight. Tungsten alloyed with about 5% to about 10% of rhenium is preferred.
  • X-ray tube 10 of FIG. 1 is further provided with rotating means located at the second end of envelope 11 for rotating anode 18.
  • the rotating means comprise rotor 24 having a shaft 23 journaled on an internal bearing support 25 which is, in turn, supported from a ferrule 26, positioned at a second end of envelope 11. Shaft 23 is secured to anode 18 through a centrally disposed opening in anode 18.
  • the stator coils for driving rotor 24, such as a stator of an air induction motor are omitted from FIG. 1. High voltage is supplied to anode 18 via a supply line, not shown, coupled to a connector 27.
  • a graphite substrate is shape formed into a desired shape by such conventional machining methods as grinding, milling, electroforming, cutting, turning, and polishing.
  • Such a machining procedure produces significant damage to the focal track region of surface 30, shown in FIG. 2, on which focal track layer 19 is deposited.
  • the aforementioned damage results from the highly brittle nature of graphite and it typically extends to a depth of about 25 to 50 micrometers on the surfaces of anode body 18 machined by a grinding operation.
  • the damage shown on the damaged layer of surface 30 of FIG. 2 in proportion to size of anode body 21, has been highly exaggerated for illustrative purposes only because the actual damage on surface 30 cannot be seen by a naked eye.
  • Adhesion between focal track layer 19 and the focal track region of surface 30 is significantly improved by substantially removing the aforementioned damaged layer from surface 30 and exposing an undamaged surface underneath it.
  • the present invention provides means for removing such a damaged layer of graphite from surface 30.
  • the graphite substrate is generally pretreated to drive off surface contaminants and adsorbed gases.
  • Such pretreatment is generally carried out by a conventional method, such as heating the substrate to a temperature above about 1800° C. in a furnace which has been initially pumped down to a fairly low vacuum to substantially eliminate oxygen after which hydrogen is fed through the furnace.
  • a conventional method such as heating the substrate to a temperature above about 1800° C. in a furnace which has been initially pumped down to a fairly low vacuum to substantially eliminate oxygen after which hydrogen is fed through the furnace.
  • Anode body 18 is preferably oxidized in air by heating it to a temperature of about 650° C. to about 900° C. for about forty-five minutes to about one hour and thirty minutes. Oxidation at about 800° C. for about one hour is most preferrred. Generally, a layer of about 50-100 micrometers is removed during the oxidation step.
  • Deposition of diffusion barrier layer 32 on focal track region of surface 31 may be carried out by any suitable method, such as chemical vapor deposition (CVD), molten electrolytic plating, DC arc plasma spraying at atmospheric and at sub-atmospheric pressure and RF plasma spraying at atmospheric and at sub-atmospheric pressure. CVD is preferred.
  • a gaseous mixture of a compound of rhenium, such as ReF 6 , and hydrogen is conveyed into a CVD chamber maintained at a pressure of about 20 to about 200 Torr, preferably at about 100 Torr.
  • the flow rate of ReF 6 is about 20 to about 40 standard cubic centimeters per minute (sccm), preferably about 30 sccm and the volumetric ratio of hydrogen to ReF 6 in the mixture is at about 100:1 to about 500:1, preferably about 200:1.
  • the mixture is preferably directed at anode body 21 placed within the CVD chamber at a velocity gradient of at least about 1050 cm/cm-sec, preferably at a velocity gradient of at least about 2000 cm/cm-sec through a slit aperture proximately positioned near rotating anode body 21, at about 5 mm to 25 mm, preferably at about 7 mm from anode body 21.
  • Anode body 21 is inductively heated to about 325° C. to about 475° C., preferably to about 350° C.
  • the mixture is energized by the heat from anode body 21 to degrade into fragments, which then adsorb and decompose on surface 31 of anode body 21 to form diffusion barrier layer 32 of rhenium shown in FIG. 4.
  • the process is conducted until about 5 to 50 micrometers, preferably about 15 micrometers, of rhenium layer 32 having microcracks, as shown in FIG. 11, is deposited on the surface of anode body 21.
  • the aforementioned thickness of 15 micrometers, under the aforementioned preferred CVD conditions, is produced in about 15 minutes.
  • the aforementioned CVD process is preferably carried out in an apparatus disclosed in U.S. Pat. No. 4,920,012 to Woodruff et al., which is incorporated herein by reference.
  • the thickness as well as morphology of barrier layer 32 is dependent upon the chemical vapor deposition conditions, such as temperature of anode body 21, the distance between the slit aperture and anode body 21, the CVD chamber pressure, and the volumetric ratio of ReF 6 to hydrogen.
  • the chemical vapor deposit morphology of barrier layer 31 may vary from a dendritic structure, shown in FIG. 8, to a smooth and dense film shown in FIG. 9.
  • the dendritic structure seen in FIG. 8 is similar to structures known in the prior art.
  • Both of the aforementioned rhenium layers are effective as diffusion barriers for preventing carbide formation of anode target material.
  • the smooth and dense rhenium barrier layer is susceptible to delamination during the pyrolytic carbon infiltration of anode 18.
  • the barrier layer shown in FIG. 9 As a result, there is a significant loss of adhesion between the barrier layer shown in FIG. 9 and graphite anode body 21.
  • an unexpectedly significant improvement in adhesion of the barrier layer to the surface of graphite anode body 21 is noted when the aforementioned rhenium diffusion barrier layer 32 having microcracks, shown in FIG. 11, is produced under the aforementioned preferred CVD conditions.
  • the microcracks, present throughout the rhenium barrier layer exhibit a morphology of closely packed individual grains having a diameter of about 8 to 10 micrometers, preferably about 10 micrometers and a height of about 5 to about 50 micrometers, preferably about 15 micrometers.
  • microcracks relieve the thermal stresses experienced by the diffusion barrier layer during the deposition of anode target layer 20 of tungsten or tungsten rhenium alloy on top of it.
  • a microcracked rhenium diffusion barrier layer 32 shown in FIGS. 4, 5, 7 and 11 exhibits a significant improvement in adhesion to the focal track region of anode 18.
  • Anode 18 of x-ray tube 10 is provided with anode target layer 20, shown in FIG. 5, by conventional deposition means, such as CVD, molten electrolytic plating, DC arc plasma spraying at atmospheric or at sub-atmospheric pressure or RF plasma spraying at atmospheric or at sub-atmospheric pressure.
  • CVD is preferred.
  • Anode target layer 20 comprises tungsten or an alloy of tungsten and rhenium. Generally, a layer of about 500 to 1000 micrometers, preferably about 750 micrometers is provided.
  • anode 18 is subjected to pyrolytic carbon infiltration process to seal off the exposed surfaces of graphite anode body 21.
  • pyrolytic carbon infiltration process By sealing off the exposed surfaces of graphite anode body 21, particulates and occluded gases within graphite anode body 21 are prevented from dusting off into high vacuum of an x-ray tube.
  • the aforementioned process also prevents electrical break-down or flashover between anode 18 and cathode 13.
  • anode 18 is maintained in furnace at a temperature of about 1000° C. to about 1100° C.
  • a gaseous mixture of methane and hydrogen is flowed through the furnace maintained at a pressure of about 1 to about 3 Torr.
  • the aforementioned process is carried out for a long time, typically for about 35 hours to produce a coating that is tightly adherent, anisotropic and is comprised of very small graphite crystallites aligned with basal planes parallel to the local surface on which they are deposited.
  • the focal track region of surface 31 is oxidized by the aforementioned oxidizing step of the present invention to expose a surface substantially free from damage produced during the shape forming step.
  • the aforementioned damage free surface is provided with a rhenium diffusion barrier layer 33, followed by anode target layer 20 of tungsten or tungsten rhenium alloy.
  • the focal track region of surface 30 is provided with the previously described microcracked rhenium diffusion barrier layer 32 followed by anode target layer 20 of tungsten or tungsten rhenium alloy.
  • Microcracked rhenium diffusion barrier layer 32 is deposited by the aforementioned CVD method.
  • a graphite substrate of x-ray target after the machining step was subjected to oxidizing step during which the surface layer damaged during the machining step was removed to expose undamaged layer underneath.
  • the substrate was oxidized for one hour @ 800° C.
  • the oxidized substrate was then subjected to chemical vapor deposition of rhenium layer @ 350° C. and 100 Torr.
  • the rhenium diffusion layer had microcracks similar to those shown in FIG. 11.
  • the anode target layer of tungsten was deposited on top of the rhenium diffusion layer.
  • An accelerated test protocol was used to focus an x-ray beam of variable power on a target area of 8.79 millimeters in length (L) ⁇ 0.75 millimeters in width (W).
  • a control test was conducted to compare the x-ray target of Example 1 with an x-ray target produced without the oxidizing step and microcracked rhenium layer of the x-ray target in Example 1.
  • a graphite substrate of x-ray target after the machining step was subjected to chemical vapor deposition of rhenium layer @ 650° C. and 50 Torr.
  • the rhenium diffusion layer had dendritic morphology similar to that of the prior art shown in FIG. 8.
  • the anode target layer of tungsten was deposited on top of the rhenium diffusion layer.
  • the aforementioned target represents a target closest to prior art.
  • a standard test protocol was used to focus an x-ray beam of variable power on a target area of 16.88 millimeters in length (L) ⁇ 1.44 millimeters in width (W).
  • the severity of the standard test is about 1/4th that of the accelerated test conducted in Example 1.
  • the ratio of kW/L(W)1/2 is more severe in the accelerated test of Table 1 than the standard test of Table 2.
  • the test was discontinued because the target experienced delamination failure after 30,828 of standard x-ray scans, which translate to about 7707 of the accelerated test scans performed in Example 1.
  • a control test was conducted to compare the x-ray target of Example 1 with an x-ray target produced without the oxidizing step and microcracked rhenium layer of the x-ray target in Example 1.
  • a graphite substrate of x-ray target after the machining step was subjected to chemical vapor deposition of rhenium layer @ 300° C. and 100 Torr.
  • the rhenium diffusion layer was a continuous layer similar to that shown in FIG. 9.
  • the anode target layer of tungsten was deposited on top of the rhenium diffusion layer.
  • the target failed due to delamination of the aforementioned continuous rhenium layer during the pyrolytic carbon infiltration process.
  • the resulting cross-section is similar to the one shown in FIG. 10.

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JP4282116A JPH05217532A (ja) 1991-10-30 1992-10-21 Ｘ線管陽極の焦点トラック構造とその製造法
AT0208592A AT399789B (de) 1991-10-30 1992-10-21 Verfahren zum herstellen einer röntgenröhrenanode und eines graphitsubstrates hiefür

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Cited By (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5420906A (en) * 1992-01-27 1995-05-30 U.S. Philips Corporation X-ray tube with improved temperature control
US5495979A (en) * 1994-06-01 1996-03-05 Surmet Corporation Metal-bonded, carbon fiber-reinforced composites
EP0756308A4 (de) * 1994-03-28 1996-12-13 Hitachi Ltd Röntgenröhre und anodentarget dafür
US5629970A (en) * 1996-01-11 1997-05-13 General Electric Company Emissivity enhanced x-ray target
WO1999045564A1 (en) * 1998-03-06 1999-09-10 Varian Medical Systems, Inc. X-ray tube rotating anode
US6078644A (en) * 1998-07-01 2000-06-20 Varian Medical Systems, Inc. Carbon-backed x-ray target with coating
US20050202272A1 (en) * 2004-03-10 2005-09-15 Mittendorf Donald L. High bond strength interlayer for rhenium hot gas erosion protective coatings
US20080101541A1 (en) * 2006-11-01 2008-05-01 General Electric Company, A New York Corporation X-ray system, x-ray apparatus, x-ray target, and methods for manufacturing same
WO2008094539A2 (en) * 2007-01-31 2008-08-07 Rajan Bamola High density low pressure plasma sprayed focal tracks for x-ray anodes
US20090086919A1 (en) * 2007-10-02 2009-04-02 Gregory Alan Steinlage Apparatus for x-ray generation and method of making same
US20100092699A1 (en) * 2007-10-02 2010-04-15 Gregory Alan Steinlage Apparatus for x-ray generation and method of making same
US20110007872A1 (en) * 2007-04-20 2011-01-13 General Electric Company X-ray tube target and method of repairing a damaged x-ray tube target
WO2012080958A3 (en) * 2010-12-16 2012-09-13 Koninklijke Philips Electronics N.V. Anode disk element with refractory interlayer and vacuum plasma focal track
US20130308754A1 (en) * 2012-05-15 2013-11-21 Canon Kabushiki Kaisha Radiation generating target, radiation generating tube, radiation generating apparatus, and radiation imaging system
US20140029728A1 (en) * 2011-04-04 2014-01-30 Vsi Co., Ltd. High-Efficiency Flat Type Photo Bar Using Field Emitter and Manufacturing Method Thereof
US20140321620A1 (en) * 2013-04-30 2014-10-30 Kabushiki Kaisha Toshiba X-ray tube and anode target
US20140355742A1 (en) * 2011-12-30 2014-12-04 Koninklijke Philips N.V. Brazed x-ray tube anode
CN104641447A (zh) * 2012-09-21 2015-05-20 西门子公司 具有阳极以生成x射线的装置
US10622182B2 (en) 2015-05-08 2020-04-14 Plansee Se X-ray anode

Citations (22)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3442006A (en) * 1962-12-17 1969-05-06 Snecma Process for welding or brazing two members of which at least one is made of graphite
GB1173859A (en) * 1967-08-28 1969-12-10 Plansee Metallwerk Improvements in and relating to Rotary Targets for X-Ray Tubes
GB1207648A (en) * 1968-08-12 1970-10-07 Plansee Metallwerk Improvements in and relating to rotary targets for x-ray tubes
US3539859A (en) * 1956-03-30 1970-11-10 Radiologie Cie Gle X-ray generator tube with graphite rotating anode
GB1247244A (en) * 1968-04-03 1971-09-22 Metallwerk Plansee Ag & Co K G Improvements in and relating to rotary targets for x-ray tubes
US3660053A (en) * 1968-12-02 1972-05-02 Schwarzkopf Dev Co Platinum-containing x-ray target
US3683223A (en) * 1968-12-16 1972-08-08 Siemens Ag X-ray tube having a ray transmission rotary anode
US3710170A (en) * 1969-10-11 1973-01-09 Siemens Ag X-ray tube with rotary anodes
US3719854A (en) * 1969-07-24 1973-03-06 Schwarzkopf Dev Co Tungsten alloy x-ray target
US3890521A (en) * 1971-12-31 1975-06-17 Thomson Csf X-ray tube target and X-ray tubes utilising such a target
US4055628A (en) * 1974-09-02 1977-10-25 The British Petroleum Company Limited Method for preparing graphite containing carbon
GB2084124A (en) * 1980-09-15 1982-04-07 Gen Electric Improved graphite X-ray tube target
US4352041A (en) * 1979-07-19 1982-09-28 U.S. Philips Corporation Rotary anodes for X-ray tubes
USRE31369E (en) * 1977-04-18 1983-09-06 General Electric Company Method for joining an anode target comprising tungsten to a graphite substrate
USRE31568E (en) * 1977-04-18 1984-04-24 General Electric Company Composite substrate for rotating x-ray anode tube
US4670201A (en) * 1983-09-20 1987-06-02 Union Carbide Corporation Process for making pitch-free graphitic articles
US4761272A (en) * 1981-09-25 1988-08-02 Union Oil Company Densified carbonaceous bodies with improved surface finishes
US4799250A (en) * 1986-01-17 1989-01-17 Thomson-Cgr Rotating anode with graphite for X-ray tube
FR2625033A1 (fr) * 1987-12-22 1989-06-23 Thomson Cgr Procede de fabrication d'une anode de tube a rayons x et anode obtenue par ce procede
US4901338A (en) * 1987-08-03 1990-02-13 Schwarzkopf Development Corporation Rotary anode for X-ray tubes and method of manufacture
US4939762A (en) * 1987-03-18 1990-07-03 Hitachi, Ltd. Target for X-ray tube as well as method of manufacturing the same, and X-ray tube
US5148463A (en) * 1991-11-04 1992-09-15 General Electric Company Adherent focal track structures for X-ray target anodes having diffusion barrier film therein and method of preparation thereof

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5246790A (en) * 1975-10-13 1977-04-13 Toshiba Corp Anode of x-ray tube
JPS59207552A (ja) * 1983-05-12 1984-11-24 Hitachi Ltd Ｘ線管回転陽極用複合ターゲットの製造法

Patent Citations (24)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3539859A (en) * 1956-03-30 1970-11-10 Radiologie Cie Gle X-ray generator tube with graphite rotating anode
US3442006A (en) * 1962-12-17 1969-05-06 Snecma Process for welding or brazing two members of which at least one is made of graphite
GB1173859A (en) * 1967-08-28 1969-12-10 Plansee Metallwerk Improvements in and relating to Rotary Targets for X-Ray Tubes
US3579022A (en) * 1967-08-28 1971-05-18 Schwarzkopf Dev Co Rotary anode for x-ray tube
GB1247244A (en) * 1968-04-03 1971-09-22 Metallwerk Plansee Ag & Co K G Improvements in and relating to rotary targets for x-ray tubes
GB1207648A (en) * 1968-08-12 1970-10-07 Plansee Metallwerk Improvements in and relating to rotary targets for x-ray tubes
US3649355A (en) * 1968-08-12 1972-03-14 Schwarzopf Dev Corp Process for production of rotary anodes for roentgen tubes
US3660053A (en) * 1968-12-02 1972-05-02 Schwarzkopf Dev Co Platinum-containing x-ray target
US3683223A (en) * 1968-12-16 1972-08-08 Siemens Ag X-ray tube having a ray transmission rotary anode
US3719854A (en) * 1969-07-24 1973-03-06 Schwarzkopf Dev Co Tungsten alloy x-ray target
US3710170A (en) * 1969-10-11 1973-01-09 Siemens Ag X-ray tube with rotary anodes
US3890521A (en) * 1971-12-31 1975-06-17 Thomson Csf X-ray tube target and X-ray tubes utilising such a target
US4055628A (en) * 1974-09-02 1977-10-25 The British Petroleum Company Limited Method for preparing graphite containing carbon
USRE31369E (en) * 1977-04-18 1983-09-06 General Electric Company Method for joining an anode target comprising tungsten to a graphite substrate
USRE31568E (en) * 1977-04-18 1984-04-24 General Electric Company Composite substrate for rotating x-ray anode tube
US4352041A (en) * 1979-07-19 1982-09-28 U.S. Philips Corporation Rotary anodes for X-ray tubes
GB2084124A (en) * 1980-09-15 1982-04-07 Gen Electric Improved graphite X-ray tube target
US4761272A (en) * 1981-09-25 1988-08-02 Union Oil Company Densified carbonaceous bodies with improved surface finishes
US4670201A (en) * 1983-09-20 1987-06-02 Union Carbide Corporation Process for making pitch-free graphitic articles
US4799250A (en) * 1986-01-17 1989-01-17 Thomson-Cgr Rotating anode with graphite for X-ray tube
US4939762A (en) * 1987-03-18 1990-07-03 Hitachi, Ltd. Target for X-ray tube as well as method of manufacturing the same, and X-ray tube
US4901338A (en) * 1987-08-03 1990-02-13 Schwarzkopf Development Corporation Rotary anode for X-ray tubes and method of manufacture
FR2625033A1 (fr) * 1987-12-22 1989-06-23 Thomson Cgr Procede de fabrication d'une anode de tube a rayons x et anode obtenue par ce procede
US5148463A (en) * 1991-11-04 1992-09-15 General Electric Company Adherent focal track structures for X-ray target anodes having diffusion barrier film therein and method of preparation thereof

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US6078644A (en) * 1998-07-01 2000-06-20 Varian Medical Systems, Inc. Carbon-backed x-ray target with coating
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ATA208592A (de) 1994-11-15
JPH05217532A (ja) 1993-08-27
AT399789B (de) 1995-07-25

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